Oki PACEMARK 4410, Руководство по обслуживанию, Страница: 12 / 215

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2. THEORY OF OPERATION
2.1 Electrical Operation
The electrical operation of the printer circuit is described in this section.
2.1.1 Summary
Fig. 2-1 shows the block diagram of the printer.
The control board is made up of the microprocessors, peripheral circuits, drive circuits, sensors and
interface connectors.
The power to the control board is supplied by the power board through the connector cord.
The power to other electrical parts is also distributed through the connectors within the control board.
2.1.2 Microprocessor and the peripheral circuit
(1) Microprocessor (IC24: 80C186-16)
This processor is a CMOS single-chip computer with integrated peripheral device functions
and a 16 bit MPU core.
The processor has a 20 bit address bus and a 16 bit data bus.
It is capable of accessing up to 4M bit program memory and 4M bit of data memory.
The following characteristics are also provided:
• High-Speed DMA Channel x 2
• Programmable Interrupt Controller
• Programmable 16-bit Timer x 3
• Programmable Memory and Peripheral Chip-Select Logic
• Programmable Wait State Generator
• Local Bus Controller
And others.
The function of this microprocessor is to provide a central mechanism for the entire printer
by executing the control program through the LSI and driver circuits.